Look I understand the perspective you are coming from. Please explain how you would explain this to children and people who decide they want to become Catholic. It is not practical to say you are joining a Papist religion, but please ignore the current Pope. To get to all this nitty gritty you would have to be well read on the topic and somewhat of a theologian. Most people would not take the time or effort.
I will tell you the jist of the way we were taught by our parents when I was a child from the time I was 2, or 3, or however far back I can remember, and later nuns - this was repeated as needed throughout childhood.
"No matter who tells you to do wrong, remember God sees it all, God see everything, He is always watching. Don't worry what your friends will say, you worry about what God will say and do to you." They would at times go into a bit more detail such as, "even if I (mom) or dad or (brother/friend/whomever) want you to do something you know is wrong, don't do it! Remember God sees it all and you will pay for it."
Anyway, this is the jist of how we were taught from far as I can tell, infancy. Very simple. It was all part of learning to pray, heaven and hell, Our Blessed Mother, guardian angels and etc - you know, was part of learning our holy religion from infancy.
As for converts, they're not from outer space ya know, they easily understand what corruption is and it is easy to explain that the recent popes are men who've corrupted themselves, that they need many prayers and that we cannot listen to them because they teach heresy. I find it somewhat amazing how easily they can initially grasp everything as regards the whole crisis situation.
I mean yes, this is a crisis, but remember, there are many, even in these days who are finding the true faith, regardless of heretical popes and regardless of heretical hierarchy for the last 60 years. Everyone on earth will indeed find the truth *if they seek it*, we have Our Lord's promise on that....then they need to keep seeking as we all must, and persevere in it no matter what. IMO, this last part is the real concern, not explaining heretical popes - I think you will find that's the easy part.